Known gas turbine engines generally include rows of circumferentially spaced nozzles and buckets. A turbine bucket generally includes an airfoil having a pressure side and a suction side and extending radially upward from a platform. A hollow shank portion may extend radially downward from the platform and may include a dovetail and the like so as to secure the turbine bucket to a turbine wheel. The platform generally defines an inner boundary for the hot combustion gases flowing through a gas path. As such, the intersection of the platform and the airfoil may be an area of high stress concentration due to the hot combustion gases, the mechanical loading thereon, and other causes.
More specifically, there is often a large amount of thermally or otherwise induced strain at the intersection of an airfoil and a platform. This induced strain may be due to the temperature differentials between the airfoil and the platform and between the pressure side and the suction side as well as due to rotational velocity loading. The induced strain may combine with geometric discontinuities in the region so as to create areas of very high stress that may limit overall component lifetime. To date, these issues have been addressed by attempting to keep geometric discontinuities such as root turns, tip turns, internal ribs, and the like, away from the intersection. Further, attempts have been made to control the temperature about the intersection. Temperature control, however, generally requires additional cooling flows at the expense of overall engine efficiency. These known cooling arrangements thus may be difficult and expensive to manufacture and/or may require the use of an excessive amount of air or other types of parasitic cooling flows.